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In 1982, a water-soluble aminoplastic resin embedding method for electron microscopy (EM) was developed to study lipids. It involves a silylation technique for processing cured resins by converting them from hydrophilic to hydrophobic status, facilitating ultra-thin sectioning. The technique offers better preservation of lipovitellin material in frog (Rana amurensis) yolk platelets, and it shows membrane ultrastructure better than traditional epoxy embedding methods. An early (1982) pseudo-colored TEM image processing technique applied to the micrographs obtained by EM of silylated aminoplastic thin sections revealed the lipovitellin molecules, in relation to the biosynthesis of new membranes in the first cleavage of the egg, with remarkable clarity and explains the lipovitellin molecules in relation to the biosynthesis of new membranes. Because the original article was written in Chinese and published in China before its open policy, many scientists may not be aware of the publication. Thus, in this short review, the essential components of the procedure are presented in English to help guide investigators who might be interested in the use of water-soluble embedding methods for lipid research. [ABSTRACT FROM AUTHOR]

A long standing problem in the manufacture of wheat-straw based composites with cost-effective formaldehyde-based resins is their poor water resistance as demonstrated by their large water thickness swell. In this study, wheat straw based medium density fiberboards were manufactured using 3 resin/wax systems: a melamine-urea-formalde-hyde resin with either low or high wax content, and a phenol-formal-dehyde resin with low wax content. The flexural properties, internal bond strength, and thickness swell of the resulting composites were evaluated and compared according to ASTM methods. The three MDF compos-ites passed the requirements for MDF in interior application, except for the MDF manufactured with the aminoplastic resin and low wax content that failed to provide acceptable thickness swell. Using the phenolic resin in combination with low wax content resulted in a higher grade MDF composite, grade 120, than with the aminoplastic and high wax content. This study demonstrates that wheat straw based MDF manu-factured with cost-effective aminoplastic and phenolic resins can have flexural properties, internal bond strength and thickness swell perfor-mance above the requirements from the American National Standards Institute.